The claim by UK Treasury Chief Danny Alexander that mortgage costs would rise in an independent Scotland is nonsensical (Alexander claims: yes to independence could mean mortgage rise, News, June 24).

This is yet another anti-independence scare story which we should become increasingly accustomed to in the run-up to the 2014 independence referendum.

Mr Alexander doesn't seem to know the difference between mortgage availability in the private sector and government bond issues. Banks base their mortgages on the interest rate set independently by the Bank of England, which in a proposed sterling zone would be exactly the same for Scotland as for England. The other issue affecting mortgage rates is the ability of banks as commercial businesses to borrow on the markets – and as we have just seen with the downgrade of 15 global banks and financial institutions, that has nothing to do with the country they are based in.

Scotland has better public finances than the UK as a whole – and lower public-sector debt than the UK, the EU and the G7 average. We boast, for example, a £1.5 trillion asset base in the North Sea, with over half of the oil and gas value still to be extracted. On Danny Alexander's illiterate economics, mortgages could go up in the rest of the UK because they would struggle as a new country without the benefit of Scottish resources. The reality is that both Scotland and the rest of the UK will be successful, independent countries.

Alex Orr

Edinburgh